I have always had problems in identifying only one best friend, because I've had a lot of friends in different periods of my life. If we talk about people that have been with me since childhood, I can say that my best friend is my neighbor, we met each other when I was 3 years old. Over the years, I have left people behind for usual life issues, some have children, others have moved to another place, and nowadays I have less best friends but good ones. (Please correct me!,thanks!)